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101.
102.
拖滞力矩主要是摩擦力矩,不但损坏零件,还容易造成盘式制动器抱死,发生意外事故,增加燃油消耗。当拖滞力矩为2Nm时,燃油消耗将增加3.1%-5。7%;当拖滞力矩为3Nm时,燃油消耗将增加4.6%-8.5%。通过实际测试,摩托车制动器的拖滞力矩在调试时应控制在0.5Nm以下为好。 相似文献
103.
主要对光纤光栅的工作原理进行了阐述,并着重以光纤Bragg光栅传感器为例介绍了这一新兴科技在传感器技术中的应用,特别阐述了光纤光栅传感器在民用结构中的用途,从而指出了光栅传感器目前最热门的研究方向是光栅传感器的实际应用研究. 相似文献
104.
高性能、低成本轻合金车轮的研究现状与发展趋势 总被引:2,自引:0,他引:2
车轮产品的轻量化、安全性和美观度越来越受到人们的重视,结合高性能、低成本轻合金车轮的研究现状,从材料开发、新工艺新技术以及计算机模拟仿真的应用等几个方面对轻合金车轮的发展趋势进行分析。 相似文献
105.
针对车辆行驶过程中不能及时发现车灯故障的问题,设计了一种新型全电子汽车灯光检测器。该检测器作为汽车制造过程中的固定电器件安装在汽车中央控制盒上,通过和车灯串联的分压电阻作为敏感元件来控制电路工作。介绍了该灯光检测器的工作原理、电路设计及性能。通过装车使用表明,该产品性能优良,且创下50万km无故障的记录。 相似文献
106.
文章从客观评价角度对制动踏板感的改进进行了阐述,针对某车型制动信心不足问题,对制动踏板感客观数据结果与行业标准校核后,发现踏板感性能各指标普遍较差。后结合整改方案,通过对真空助力器、制动主缸等结构及参数的变更分析,制定对比验证方案,以验证制动系统优化方案可行性,并给出试验结论及建议。 相似文献
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文中介绍了轻型多旋翼无人机凭借体积小、质量轻、操作简单、成本低等优势成为了助力海事监管效能提升的重要帮手.但由于无人机参与执法存在一定的安全隐患,在使用中应加强风险管理并提出建立健全无人机使用安全管理机制;强化专业人才队伍建设;加强无人机飞行安全保障;强化无人机投保续保意识;推动海事无人机行业标准制定的风险管理对策. 相似文献
109.
As decision-makers increasingly embrace life-cycle assessment (LCA) and target transportation services for regional environmental goals, it becomes imperative that outcomes from changes to transportation infrastructure systems are accurately estimated. Greenhouse gas (GHG) reduction policies have created interest in better understanding how public transit systems reduce emissions. Yet the use of average emission factors (e.g., grams CO2e per distance traveled) persists as the state-of-the-art masking the variations in emissions across time, and confounding the ability to accurately estimate the environmental effects from changes to transit infrastructure and travel behavior. An LCA is developed of the Expo light rail line and a competing car trip (in Los Angeles, California) that includes vehicle, infrastructure, and energy production processes, in addition to propulsion. When results are normalized per passenger kilometer traveled (PKT), life-cycle processes increase energy use and GHG emissions up to 83%, and up to 690% for smog and respiratory impact potentials. However, the use of a time-independent PKT normalization obfuscates a decision-maker’s ability to understand whether the deployment of a transit system reduces emissions below a future year policy target (e.g., 80% of 1990 emissions by 2050). The year-by-year marginal effects of the decision to deploy the Expo line are developed including reductions in automobile travel. The time-based marginal results provide clearer explanations for how environmental effects in a region change and the critical life-cycle processes that should be targeted to achieve policy targets. It shows when environmental impacts payback and how much reduction is achieved by a policy-specified future year. 相似文献
110.
Despite the growing development of tools that can integrate land use and transport, the desired integration is still illusive in daily practice. To address this gap, the current study uses spatial metrics, a set of methods traditionally used for studying changes in the spatial structure of landscapes, which are translated into the domain of transport planning. It examines how spatial metrics can be integrated into “Land Use Transport” strategy-making, and how useful they are according to the practitioners’ perceptions. A Light Rail Transit corridor in Granada (Spain) provides the empirical focus of this research. Land use characteristics such as: land use mixing, land use diversity and green areas connectivity were successfully studied using spatial metrics, and they were used to map three “Land Use Transport” strategies: (i) proximity dynamics and non-motorised modes; (ii) modal shift from cars to Light Rail Transit system; (iii) shared spaces between motorised and non-motorised modes. Practitioners perceived that spatial metrics could improve the “Land Use Transport” strategy-making process in comparison with traditional methods used in practice. However, certain shortcomings related to the usability of spatial metrics are also highlighted and discussed. This study concludes with a reflection on research challenges for adapting spatial metrics to transport practice. 相似文献